Missouri Revised Statutes Title XXXI. Trusts and Estates of Decedents and Persons Under Disability § 474.240. Share of omitted children, how determined

1. If a testator fails to provide in his will for any of his children born or adopted after the execution of his will, the omitted child receives a share in the estate equal in value to that which he would have received if the testator had died intestate, unless:

2. If at the time of execution of the will the testator fails to provide in his will for a living child solely because he believes the child to be dead, the child receives a share in the estate equal in value to that which he would have received if the testator had died intestate.

3. An illegitimate child is not a child of a male testator, for the purposes of this section, unless the testator, during his lifetime or in the will, recognized that the child was his.

4. In satisfying a share provided in this section, the devises made by the will abate as provided in section 473.620.